add region_name to auth plugin parameters

If endpoint is not specified, then auth plugin will request to keystone
to get target endpoint, however, we don't provide region name for it,
this will cause critical issue in multiple region scenario.

Change-Id: I99ceafec25072988435018ca1affbd778ca9b22f
Closes-Bug: #1439553

ceilometerclient/client.py

@@ -180,6 +180,7 @@ class AuthPlugin(auth.BaseAuthPlugin):
                 'insecure': strutils.bool_from_string(
                     self.opts.get('insecure')),
                 'endpoint_type': self.opts.get('endpoint_type'),
+                'region_name': self.opts.get('region_name'),
             }
 
             # retrieve session
@@ -316,6 +317,7 @@ def get_auth_plugin(endpoint, **kwargs):
         token=kwargs.get('token'),
         endpoint_type=kwargs.get('endpoint_type'),
         insecure=kwargs.get('insecure'),
+        region_name=kwargs.get('region_name'),
         cacert=kwargs.get('cacert'),
         tenant_id=kwargs.get('project_id') or kwargs.get('tenant_id'),
         endpoint=endpoint,

ceilometerclient/tests/unit/test_client.py

@@ -81,6 +81,7 @@ class ClientTest(utils.BaseTestCase):
             'service_type': None,
             'token': '1234',
             'endpoint_type': None,
+            'region_name': None,
             'auth_url': 'http://no.where',
             'tenant_id': None,
             'insecure': None,